The avascular plane of the Achilles tendon: a quantitative anatomic and angiographic approach and a base for a possible new treatment option after rupture.

INTRODUCTION: Achilles tendon ruptures, especially ruptures caused by pathologic conditions and also by achillotendinitis are often attributed to the alleged hypovascularisation of the Achilles tendon. Anatomic studies often mention an avascular plane. The purpose of this study was to re-investigate the arterial supply of the Achilles tendon. MATERIAL AND METHODS: Lower legs of 28 anatomic specimen were injected with a radiologic contrast agent and subsequently an arterial angiography was performed. Afterwards the legs were embalmed and later anatomically dissected. The origin of arteries entering the paratenon of the tendo calcanei branching off from either the anterior (TA) or the posterior tibial artery (TP) was determined. The distance between the points of commencement of these nutrient arteries and a specific reference point, i.e. the insertion of the Achilles tendon into the tuber calcanei, was measured digitally on the radiographs and again with a slide-gauge on the dissected specimens. RESULTS: As revealed by angiographic analysis, the TA gave off 5 vessels (v) at a frequency and median distance to the tuber calcanei (in cm) of v1: 50%, 6.01 cm; v2: 39.3%, 7.88 cm; v3: 35.7%, 9.71 cm; v4: 17.9%, 12.7 cm; v5: 10.7%, 14.6 cm. The TP contributed to the arterial supply of the Achilles tendon by means of 7 inserting arteries branching off at a frequency and mean distances of v1: 67.9%, 4.53 cm; v2: 60.7%, 6.97 cm, v3: 50%, 9.58 cm; v4: 35.7%, 10.89 cm; v5: 25%, 12.65 cm; v6: 10.7%, 16.94 cm; v7: 3.6%, 18.7 cm proximal to the tuber calcanei. However, due to the small diameter of these branches, by anatomic dissection no nutrient arteries commencing from the TA could be detected. On the other hand, a maximum of 7 vessels originating from the TP, larger than the former vessels, had been also revealed by anatomic dissection (frequency and mean distances, v1: 100%, 6.8 cm; v2: 82.1%, 7.7 cm; v3: 71.4%, 9.5cm; v4: 35.7%, 11.3 cm; v5: 17.9%, 9.9 cm; v6: 7.1, 10.5 cm; v7: 3.6%, 12.0 cm). CONCLUSION: A dense net of small arteries inserts into the paratenon of the Achilles tendon in its lower 20 cm. The angiographic method was more specific and showed vessels that could not be identified as arteries originating from the TA by macroscopic anatomic dissection.

Elective abdominal aortic aneurysm repair: does the aneurysm diameter influence long-term survival?

OBJECTIVES: The aim of this study was to investigate whether initial abdominal aortic aneurysm (AAA) diameter influences long-term survival after elective repair. DESIGN: Retrospective analysis of database. MATERIAL AND METHODS: Between March 1995 and December 2006, a consecutive series of 895 patients underwent elective treatment of an AAA either by open surgical or endovascular repair. An AAA diameter of 5.5cm was chosen as threshold to distinguish between small and large aneurysms, according to the definition given by the UK small aneurysm trial. Patient characteristics and distribution of basic risk factors were assessed. Survival estimates (Kaplan-Meier) and Cox proportional hazards regression results are reported. RESULTS: Patients with small aneurysms were more likely to survive the first 6 years after AAA repair, even after adjustment for treatment modality and baseline risk factors. After adjustment for age and sex aneurysms with smaller diameter were related to a lower risk of death (p<0.0016). CONCLUSIONS: Patients with small aneurysms (< or =5.5cm) have an improved long-term survival than patients with larger aneurysms.